1. Field of the Invention
The present invention generally relates to a touch panel, and more particularly to a touch panel having a double-layer electrode structure.
2. Description of Related Art
Touch screens are input/output devices which adopt sensing technology and display technology, and which have been widely employed in electronic devices such as portable or hand-held electronic devices.
A capacitor-based touch panel is a commonly used touch panel that utilizes a capacitive coupling effect to detect touch position. Specifically, capacitance corresponding to the touch position changes and is thus detected, when a finger touches a surface of the touch panel.
Referring to FIG. 1A and FIG. 1B, FIG. 1A shows a cross-sectional view of a conventional touch panel 100 and FIG. 1B shows a manufacturing process of the conventional touch panel 100. As shown in FIG. 1A and FIG. 1B, a plurality of first electrodes 112 are disposed on an upper surface of a first substrate 110, and a plurality of second electrodes 122 are disposed on a bottom surface of a second substrate 120. Further, the upper surface of the first substrate 110 is adhered to the bottom surface of the second substrate 120 by an optically clear adhesive layer 130, wherein the first electrodes 112 and the second electrodes 112 could be orthogonal to each other.
In the conventional touch panel 100 mentioned above, a plurality of first conductive lines 114 and a plurality of second conductive lines 124 must be respectively formed on periphery areas of the upper surface of the first substrate 110 and the bottom surface of the second substrate 120 by screen printing process or yellow light manufacturing process, such that the first conductive lines 114 and the second conductive lines 124 are electrically connected to the first electrodes 112 and the second electrodes 122 respectively, in order to transmit sensing signals of the touch position. However, the design and manufacturing process of the conductive lines in the conventional touch panel are complicated, often resulting in high manufacturing costs and low productivity.
A need has thus arisen to propose a novel touch panel to overcome deficiencies of the conventional touch panels.